Broaching machine



H. ii BLANCHARD. BROACHING MAOH INE. APPLICATION FILED AUG-14. I922.

- 15,464. 2 SHEETS-SHEET l.

Reissued 0,0910, 1922.

H. E. BLANCHARD.

BROACHING MACHINE. APPLICATION FILED AUG-14.1922.

Reisued Oct. 10,1922.

Reissued Oct. 10, 1922.

Rel. 15,4 4;-

HARRY E. BLANCHARD, OF ZHIAR'LFORD,

co-N- Ec'rIoUrfAssIeNon TO LAPoINTE MACHINE 1001. COMPANY, or HUDSON, MASSACHUSETTS, A CORPORATION or MAINE.

BROACHING MACHINE.

Original No. 1,295,957, dated March 4, 1919, Serial No. 203,079,v filed November 21, 1917. Application for reissue filed August 14, 1922. Serial No. 581,890.- 3 7 T all w homit may concern:

Be it known that I, HARRY E. BnANoHARn, a citizen of the United States, Hartford, county of Hartford, State of ionnecticut, formerly of Hudson, Mass, have invented new and useful Broaching Machines, of which the following is a speclfication. I I I This invention relates to a machine for external broaching, and the principal objects thereof are to provide a construction by which the article to be broached is drawn through a plurality of breaches arranged in alignment and adapted to operate one after the other on the article as it is passed through them, and particularly to provide for pulling the article itself through the stationary broaches so asto'aVOid all possibility of chattering and materially acili? tate the operation. Another object of the invention is to provide an efficient arrangement whereby repeated broaching. operations can be performed on the same article during its passage through the machine, thus saving a great deal of-time and also to provide for performing operations all around the article simultaneously, thus saving time in. another way. The invention also involves improvements in detailsof construction and relative arrangements of parts as will appear.

Reference is to be had to the accompanying drawings, in which v Fig. 1 is a plan of a machineconstructed in accordance with this invention;

Fig. 2 is a fragmentary side view on enlarged scale showing someparts insection on a central vertical plane;

broach holder and broaches on the line-;3-3 of Fig. 4 and on enlarged scale; e 1 Fig. 4 is an end view of the same, and Fig. 5 is a side view of a drawing roll showing the character of work that. can be performed onthis machine. I

The machine is shown as. mounted on a frame 10 and provided with tight and loose pulleys 11 for operating a driving shaft 12. This shaft has two pinions 13 and 14 adapted to mesh respectively with a gear 15 and a. gear 16, which lattermeshes with a gear residin at 17. The gear-'15 is provided with a clutch hub 18 and the gear 17 with a clutch. hub

d di fe nt p ds. ment'with them is a central clutch member 20 which has a nut insidefixed to it for engaging the operatin screw. 21 and moving it longitudinally." 'T is central clutch member 20 is shown neutral position in Fig. 2, but it can be movedin either direction along the nut to whichit is slidingly keyed so as to move the screw, in either directlon. This member 20 is operated by a shift rod .19. It will'be obvious that these two hubs 18 and 19 are rotated in'opp'osite directions Mounted in align- 22 slidablymounted' ,onthe frame and con- 1 to the hub 18 to cause the screw 21 to move to the right with a slow cutting feed. At the end .ofthis screw it is secured to a slide 30 by a key 31 and aunt 32. This slide has a projection 33 moving, .of course, with the screw. When the screw has completed its operative motion to the right as far as it is intended to go, the projection 33,engages a dog 34 on therod 22 and shifts it to the right, which 'reverses the operation by mov in the reverse direction at a comparatively rapid speed. unt1lthe projection 33 strikes a,d og 35 adjustablymountedon the rod 22, wh10h. brings the clutch member outto neusliding head is provided with a center rest- 42 screwed into it for supporting one end ing the clutch member 20.to the right'so that its conicalv part ,clutches'into the hub 19 frictlonally. The screw is then: operated Fig. 3 is a central sectional view of the' of the work A which in thisfcase is in the form of a roll for a drawing machine. The

vertically sliding head 38v is also provided with a plate L3 which is connected by rods H with a slide 45. This latter slide is adapted to move on ways .46 constituting part of the frame of thema'chine andthe slide 30rand plate43 slide-on ways 47 lo cated in stationary position on the machine.

To the slide 45 is fixed a center rest &8!

for supporting the opposite end of the work so that .both' ends of the work are supported solely by the two centers 42' and 48 which move positively together and slidewith the screw absolutely. I j Mounted on the frame is a st atlona'ry holder 50' which constitutes the broach or *tool holder. This has two opposite circular heads 51 connected by integraltmen ibers 52 and is also provided with a' removable plate 53 atone end having grooves corresponding i with the grooves tobe formed on the work,

andia removable plate 54 at the other end having a passage forpermitting the work to pass through it, and having a registering key 59. The work .is performed by a plurality of external broaches 55 all'ofsubstantially the same character except that jset 'of broaches is removable and replace-" those toward the right are slightly smaller in internal diameter than the next ones to the left. They are formed of hardened steel and are provided with internally projecting teeth for cutting the grooves a. on

i the drawing roll A or any other .workthat is to be performed. They are held in position by bolts '56 secured between the two plates' 53 and 54', and of course, located in stationary position while they are spaced apart'by collars 57 mounted on the/bolts. Being spaced,.the chips have a chance to fall down between them. Thus the whole able as one piece.

The operation of moving the screwback and forth has been described and all that need be repeatedis that the machine is automatically. stoppedwiththe members 43and 45 at the extreme left so that the center 42 l projects throughjthe left end of the series of broaches. The old work is taken out and the the new work placed in position. Then the machine is started by the lever 26, the belt 4 having been shifted on the tight pulley ,as will be obvious. This results in pulling the work through the broaches, both ends" of the work being held firmly, accurately guided, and positively moved forward. In this way there is no material chancefor vibration or chattering and the work of numerous tools is performedby a single-operation.-

A receptacle foroil 6Q is shown and means is provided for circulating the oil,but that is not shown anddoes not constitute part of this invention.

Although I have illustrated and described broaches toward said means.

only a single form of the invention, I am aware of the fact that modifications can be made therein by any person skilled in the art without departing from the scope of the invention as expressed in the claims. Therefore I do not. wish to belimited to all the cletailsof construction hereinshown and described, but what I: do claim is 1. In a broaching machine, the combination of a stationary broach holder, a plurality of broaches carried by said holder provided with internal" cutting surfaces, and means beyond one end of the broach holder for pulling the work through the holder and 2. In a broaching machine, the combination of a stationary broach holder having heads at its ends and spaced integral members connecting them, a plate fitting in said broach holder at one end, means for supporting and spacingapart a plurality of broaches, in alignment with said plate, a plate at the other end of the series of broaches,

andbolts'for securing said broaches and plates in position in the holder 3. In a broaching machine, the combination'of a stationary broach holder having heads at its ends and a skeleton frame connectlng them,- means 'forsupporting a plurality of broaches insaid holder and spacmg them apartto provide spaces between the broaches and through the frame for the escape of chips, bolts for securing said broaches together, and means fordrawing the work through the broaches.

4:. In a broaching machine, the combination of a stationary broach holder having heads at its ends, two plates fitting in said broach holder, one in each of said'heads, and .means supported by said plates for carrying a plurality of broaches between them and for securing the plates rigidly togetherfone of said platesbeing keyed to its ead to prevent turning.

5. In a broaching machine, the combination of a stationary broach holder, a pairof plates carried by the ends of said broach holder, and means for rigidly connecting said plates and for supporting a series of broaches between them, one of the heads having means 'against'which the corresponding plate engagesso that the work can be drawn through the broaches in the direction toward that head without. displacing the' plate, said plate also having a passage therethrough having a series of grooves corresponding with the cutting surfaces o-f'thebroa ches.

6. In a broaching machine, the com'bination of a stationary broach holder having means for holding a plurality of external broaches, two slides on opposite sides of said broach holder each having a center point forholding the'work, said slides being connected together, and means for moving said slides in a direction to draw the work axially way throug one of .said center long enough to extend all the through the broaches, points bein means for supporting and spacing apart a plurality of broaches in alignment, means for supporting the work and drawing it through the broaches comprising a non rotatable screw, a nut engaging the screw, means for turning said nut in either direction to move the screw back and forth, means for automatically reversing the nut after the workin stroke has been completed, and means or then stopping it to bring the work back to its initial position beyond the broaches and permit it to be removed.

8. Ina broaching machine, the combination of stationary broach holder having means for supporting and spacing apart a plurality of broaches in alignment, means for drawing the work through the broaches comprising a slide, transverse ways across said slide, a head transversely adjustable on said Ways, a center support carried by said head, a screw non-rotatably fixed to said slide, a nut engaging the screw, and means for turning said nut in either direction to move the screw back and forth.

9. In a broaching machine, the combination of a broach holder having means for supporting a broach, means for supporting the work and drawing it through the broach, means for automatically reversing the work after the working stroke has been completed, and means for then stopping it to bring the work back to its initial position beyond the broach and permit it to be removed.

10. In a broaching machine, the combination with abroach holder having a recess therein, of two plates fitting in the ends of said recess, andmeans for fixing a series of broaches to said plates independently of the holder, whereby they are movable and replaceable as a whole.

11. In a broaching machine, the combination of means for supporting the work and a broach, and means for causing a relative reciprocating motion thereof comprising a non-rotatable screw, a nut engaging the screw, means for turning said nut in either direction to move the screw back and forth, means for automatically reversing the work after the working stroke has been completed, and means for then stopping it to bring the partsback to initial position.

12. The combination of a stationary broach holder having heads at its ends and spaced integral members connecting them, a plate fitting in said broach holder at one end, a plurality of broaches located in alignment the series of broaches to permit with said plate, means for supporting said, broaches and spacing them apart, a plate at the other end ofthe series of broaches, and

bolts for securing said broaches and plates in position in the holder.

18. The combination of a stationary broach holder having heads at its ends and a skeleton frame connecting them, a pluralitv of broaches in said holder having said broaches and spacing them apart to provide spaces between the broaches and through the frame for the escape of chips, bolts extending through said holes for securing said broaches together, and means fordrawing the work through the broaches.

14. The combination of a. stationary broach holder having, heads at its ends, two plates fitting in said broach holder, one in each of said heads, a plurality of broaches between said heads, and means supported by said plates for carrying the broaches be tween them and for securing the plates rigidly together, one of said plates being keyed to its head to prevent turning.

15. The combination of a stationary broach holder, a pair of vplates carried by the ends of said broach holder, a series of broaches between them having a circular series of internal grooves forming cutting surfaces, and means for rigidly connecting said plates and for supporting said broaches, one of the heads having means against which the cor responding plate engages so that the work can be drawn through the broaches in the direction toward that head without displacing the plate, said plate also having a passage therethrough having a series of grooves corresponding with the cutting surfaces of the broaches.

16. The combination with a broach holder having a recess therein, of two plates fitting in the ends of said recess, a series of broaches, and means for fixing said broaches to said plates independently of the holder, whereby they are 'movable and replaceable as awhole.

17. The combination with a broach holder having a recess therein, of two plates fitting" in the ends of said recess, a series of broaches, and means for fixing said broaches to said plates independently of the holder, whereby they are movable and replaceable as a whole, said means comprising bolts passingthrough the plates and broaches from end toend of the series, said broaches being perforated at points beyond their cutting surfaces to receive the bolts.

18.; set of broaches eachhaving a central lnternally grooved opening provlding a circular series of longltudinal cutting edges, the openings gradually varying in size from one end of the series to the other, the broaches also having registering. perforations beyond said openings, spacing collars between each two adjacent broaches, and a set of bolts passing through said per- .holestherethrough, means for supporting forations for holding the broaches and 001- plate havin lars as a unit. 19. As an article of manufacture, an eX- ternal broaehing die comprising a plate of j" 5 hardened steel having a central perforation provided With a circle of grooves in its edge,

forming teethhaving cutting edges, said HA RRY E.

g, perforations 'therethreughput-f side said perforation for receiving ,fas'ten-H, ingbolts; '1 v10 In testimony. whereof, I- have hereunto afiiXed my signature. 

